In 1998 the Bureau of Primary Health Care (BPHC), the part of the Health Resources and Services Administration that oversees all federally-funded health centers, began a major 6-year Health Disparities Collaborative effort designed to reduce health disparities and improve the quality of care in health centers. The initiative aims for rapid quality improvement through the Institute for Healthcare Improvement's Breakthrough Series methodology, the MacColl Institute for Healthcare Innovation's Chronic Care Model, and regional or national learning sessions. Previous work by the University of Chicago indicated that care improved in the first year of the Collaborative, but that health centers had identified several challenges to further quality improvement. Therefore, the investigators have three specific aims: 1) To determine if the Health Disparities Collaboratives (HDC) have improved the quality of care and outcomes of patients over the six-year span of the initiative. 2) To determine ways to enhance the effectiveness, sustainability, and spread of the HDC, with a special emphasis on seeking to understand and improve incentives and assistance for both leaders and other staff at the health centers. 3) To evaluate the costs and cost-effectiveness of the HDC, in order to assess whether quality of care improvements that are effective, sustainable, and capable of spread are also viable financially from health center and societal perspectives. Investigators plan to study approximately 200 health centers in the Midwest and West Central regions of the country. On a subset of 32 health centers already involved in a Diabetes Collaborative evaluation, further chart review and patient surveys for performance indicators will be obtained. On the universe of 200 health centers, leaders and staff will be given written surveys with an emphasis on determining incentives and assistance that would be helpful, and semi-structured interviews will be performed on a subsample. Investigators will perform general cost descriptions, and use formal, well-validated models for diabetes cost-effectiveness analyses of the Collaborative. This project will help inform future efforts to improve chronic care management in health centers.